1. Field of the Invention
The present invention relates generally to head restraint systems, and more particularly, but not by way of limitation, to head restraint systems for use by drivers of racecars, such as those used in the NASCAR racing program.
2. Description of the Prior Art
Fatal neurological damage, i.e. frontal lobe contusions, rupturing of blood vessels, and tearing of nerves, of the brain ensues after many high speed frontal race car collisions. Such fatalities are more prevalent during practice conditions than true racing situations, due to the fact that during competition, much of the car""s forward momentum dissipates due to numerous collisions with other drivers before the end of the accident. On the other hand, when dealing with practice situations, and sometimes during actual race conditions, all of the energy of the high speed is transferred between one car and a wall of the racetrack in a full frontal impact. As seen from NHTSA and STAPP Car Conference deceleration studies, approximately 7% of racecar major deceleration crashes were front impact collisions and there is a major need for protection. For everyday drivers, peak decelerations averaged from 40 Gs to 60 Gs. For racecars, this deceleration topped out at over 160 Gs. At peak decelerations of greater than 40 Gs, severe brain injury is likely to ensue, therefore a need for some type of protection of the head from these extreme forces on the brain caused during racecar deceleration exists.
A number of restraint systems are currently available.
One type of restraint system is the use of air bags which can lessen the force on the head after a collision. Air bag technology is typically not usable for racecars, however, because the air bags have been found not to be efficient at the very high speeds of 200 mph or more encountered by racecars. Also, using air bags at high racing speeds would create the risk of abruptly stopping the head in the forward motion and causing severe recoil of the head, resulting in a major skull-brain collision. Also, entrapment of the driver within the vehicle can ensue after the air bag deploys, thus not allowing the driver to escape from a dangerous vehicle which may be on fire.
Another existing restraint system is the use of a five-point harness type seatbelt system which keeps the body in the seat very tightly and protects the upper torso from injury. However, a five-point seatbelt restraint system still leaves the head free and mobile.
Another restraint system known as HANS(copyright) (Head And Neck Restraining System) available from Hubbard/Downing Inc., of Atlanta, Ga., anchors the helmet and head with straps. It prevents forward movement in a crash, but it does not absorb the impact; there is still a danger of brain/skull collision. Also, the HANS system impairs the driver""s lateral vision.
Another apparatus which bears some superficial similarity to the present invention is that shown in Townsend, U.S. Pat. Appl. Publ. No. 2001/0002087A1. The Townsend system essentially uses a conventional seat belt mounted on in inertially lockable reel type seat belt tensioner. Normal slow head movement and extension of the belt is allowed. A rapid head movement upon impact of the vehicle with an obstacle causes the tensioner to lock the belt in place, and only a slight forward movement beyond the locking point is permitted due to whatever elasticity is inherent in the seat belt material. Total forward movement of the head upon vehicle impact is in the range of 1 to 4 inches. The primary purpose of the Townsend device is to prevent the head from pivoting forward beyond the body, thus reducing neck injury. The shortcoming of the Townsend device is that it does very little to reduce deceleration forces on the head, and even though the head does not crash into the dash or steering wheel, the brain impact within the skull is still severe.
Thus, it is seen that there is a continuing need for a head restraint system for use by racecar drivers which does not impede the driver""s comfort and safety during normal use, and which prevents fatal head injury to the driver during a frontal impact.
A head restraint apparatus for a driver of a vehicle is provided which includes a helmet for receiving the driver""s head, an energy dissipating extendable restraining lanyard, a first connector connecting the lanyard to the helmet, and a second connector operably associated with the lanyard for connecting the lanyard to the vehicle, so that upon impact of the vehicle with an obstacle the lanyard extends and dissipates energy to dampen a deceleration shock transmitted to the driver""s head. The restraining lanyard has a fixed pre-impact length, and has a threshold tension load beyond which the lanyard extends.
The lanyard may include any one of a number of shock absorbing devices of the type previously developed for use as personal descent restraints for mountain climbers and for workers working at high altitudes who are at risk of falling. These various shock absorber constructions, when utilized with the head restraint apparatus of the present invention, allow the driver""s head to begin moving forward once a tension load on the restraining lanyard exceeds a first design level. The head and helmet move forward through a pre-determined extension distance, while the shock absorber mechanism dissipates much of the kinetic energy of the forwardly moving head and helmet, so as to reduce the deceleration shock loadings imposed upon the driver""s head to a level low enough that severe head injury will not occur.
The present system prevents brain injury because it allows the head to move forward a substantial distance, but at a reduced speed, which prior art devices such as the HANS(copyright) device and the Townsend device of U.S. Pat. Appl. Pub. 2001/0002087A1 do not do. Allowing the head to move forward, but at a reduced speed, is the only way to slow down forward movement of the brain relative to the skull. Prior art devices, in contrast, completely prevent the head from moving forward, thereby preventing neck injury but not reducing brain injury.
Preferably, the head restraint system includes a quick release mechanism which allows the driver to quickly escape from the helmet after a crash. The quick release mechanism may be incorporated into the existing five-point quick release mechanism of traditional safety harnesses, so that the helmet restraint system is released at the same time the safety harness is released.
The head restraint system also preferably utilizes a connection assembly between the restraining lanyards and the helmet, which will allow the driver to rotate his head in order to look laterally, so that the driver""s lateral vision is not impaired.
Accordingly, it is an object of the present invention to provide a head restraint system for use by racecar drivers which will reduce the deceleration shock forces encountered by the driver""s head during a frontal crash.
Another object of the present invention is to reduce driver injury and fatalities in racecar crashes.
Still another object of the present invention is the provision of a head restraint system from which the driver can quickly escape.
Still another object of the present invention is the provision of a head restraint system which allows the driver to have normal lateral head movement during normal usage.
And another object of the present invention is the provision of a head restraint system which is relatively lightweight so as not to induce driver fatigue.
Still another object of the present invention is the provision of a head restraint system which is economical to manufacture.
Other and further objects, features and advantages of the present invention will be readily apparent to those skilled in the art upon a reading of the following disclosure when taken in conjunction with the accompanying drawings.